Mechanobiology of the relocation of proteins in advecting cells: in vitro experiments, multi-physics modeling, and simulations.

Cell motility-a cellular behavior of paramount relevance in embryonic development, immunological response, metastasis, or angiogenesis-demands a mechanical deformation of the cell membrane and influences the surface motion of molecules and their biochemical interactions. In this work, we develop a fully coupled multi-physics model able to capture and predict the protein flow on endothelial advecting plasma membranes. The model has been validated against co-designed in vitro experiments. The complete picture of the receptor dynamics has been understood, and limiting factors have been identified together with the laws that regulate receptor polarization. This computational approach might be insightful in the prediction of endothelial cell behavior in different tumoral environments, circumventing the time-consuming and expensive empirical characterization of each tumor.

Role of VEGFs in metabolic disorders.

Obesity and metabolic disorders are important public health problems. In this review, the role of vasculature network and VEGF in the adipose tissue maintenance and supplementation is discussed. Angiogenesis is a key process implicated in regulation of tissues homeostasis. Dysregulation of new blood vessels formation may be crucial and contribute to the onset of several pathological conditions, including metabolic syndrome-associated disorders. Adipose tissue homeostasis is fine regulated by vascular network. Vessels support adipose structure. Vasculature modulates the balance between positive and negative regulator factors. In white adipose tissue, vascular endothelial growth factor (VEGF) controls the metabolic activities of adipocytes promoting the trans-differentiation from white to beige phenotype. Trans-differentiation results in an increase of energy consumption. VEGF exerts an opposite effect on brown adipose tissue, where VEGF increases oxygen supply and improves energy expenditure inducing the whitening of adipocytes.

Monoamine neurotransmitters and movement disorders in children and adults.

Neurotransmitter disorders comprise a rapidly expanding phenotypically and genetically heterogeneous group. Most of these disorders start in infancy through to childhood, although some forms may arise in adolescence and adulthood, and have various presentations. They may be overlooked if the phenotype leads to misdiagnoses involving various combinations of developmental disorders, hypotonia and movement disorders (dystonia, hyperkinesia, parkinsonism) or other clinical manifestations, such as sleep alterations and mood disorders. Neurotransmitter metabolite levels in cerebrospinal fluid (CSF) may help us to analyze and better understand the metabolic cascade and changes in dopamine and serotonin synthesis, and also guide genetic testing. Indeed, it is important to recognize these disorders in their early stages as they can be greatly improved by drug treatments, and if clinical responses are insufficient, then other agents that may enhance neurotransmission, such as serotonergic drugs and tetrahydrobiopterin (BH4) supplementation, could be considered. Also, a precise genetic diagnosis should be established by gene panels for dystonia, SNP microarrays and whole-exome sequencing. The present brief survey aims to review the present state of the art for the most commonly described and rare disorders of dopamine and serotonin, as well as cofactor deficiencies and dysfunctions, with an overview of clinical features, diagnostic strategies and treatments. Moreover, although these are mainly disorders of infants and children, many may nevertheless reach adulthood; thus, their evolution and treatments should be well known not only by pediatricians, but by neurologists as well, as the latter may be in charge at the stage of diagnosis (rarely) and during the follow-up of these rare patients.

What is the "ideal" grading system for the junior surgery clerkship?

BACKGROUND: There is currently no consistency in grading systems for clinical clerkships across medical schools. METHODS: Surgery clerkship directors were surveyed regarding their current grading categories, distribution of grades across levels, and opinions about the "ideal" grading system. RESULTS: Responses were received from 103 of 134 schools (77%). The following grading systems were employed: numerical scores, 1%; points, 1%; pass/fail, 5%; letter grades, 19%; and descriptor terms, 74%. Institutions used the following number of grading categories: 2, 5%; 3, 18%; 4, 35%; 5, 37%; 6, 3%; and 7, 1%. There was considerable variation between schools in frequency distributions across levels. Half of clerkship directors were satisfied with their system, and most considered an ideal system to consist of 4 or 5 descriptors. CONCLUSIONS: We believe an optimal clerkship grading system should consist of 4 or 5 categories. A 3-level system does not sufficiently discriminate, and with more than 5 categories the lowest levels are rarely used. Grades must be reported with clear information about their significance in each institution.

[Diagnostic approach to popliteal venous aneurysm]. / L'approccio diagnostico all'aneurisma venoso popliteo.

Venous aneurysms are rare vascular abnormalities and are often described in patients presenting with pulmonary embolism. The occasional real time ultrasound examination of an aneurysm of venous system in the popliteal fossa has focalized our interest in the diagnostic approach of this entity. In our experience and in the literature the physical examination is usually negative while the ultrasound gives high quality imaging combined to a Doppler evaluation, so this kind of diagnostic tool is desirable as a first approach. Both morphology and flow hemodynamics can be detected in a non invasive way. About wall aspect and surrounding tissue is underlined the MRT and CT scanning, the thrombotic extension is well inspected. The venography is the definitive study and should always be performed because it is the most reliable examination and specific until the sac of aneurysm is filled from the contrast. However this diagnostic modality is useful in the patient undergoing surgical repair.

[The popliteal artery entrapment syndrome. Clinical experience]. / Sindrome da intrappolamento dell'arteria poplitea. Esperienza clinica.

The authors report their experience in treating three cases of popliteal artery entrapment. The analysis is based on the onset and the gap of time between the symptoms and the diagnostic certainty referred to the age of the patients. The diagnostic approach and follow-up is discussed including magnetic resonance of popliteal fossa. The surgical approach was constantly a shaped dorsal incision, and the reconstruction was performed in two cases with carbon coated dacron grafts of 6 mm diameter for the inadequacy of veins available. Any true aneurysm formation was identified. All grafts are patent on follow-up and the viability of the popliteal artery that underwent to simply myotomy is confirmed too by doppler ultrasound. Any recurrence of symptoms is recognized, in only one case was observed a concomitant entrapment in the other leg, not treated now is underlined. The advantage available for the patient in a physiokinetic therapy program, forerunner of a complete functional restoring, especially in athletic patients.

[A parotid arteriovenous fistula of nontraumatic origin. A case report]. / Fistola arterovenosa parotidea di origine non traumatica. Case report.

The authors report their experience of a case of non traumatic arteriovenous communication of the parotid region in an adult subject. They confirm that its manifestations in grown-ups are to be linked with an inactive angiodysplastic field. The diagnostic approaches in the face of a hybrid symptomatology and the therapeutic choices are described. Moreover, an aesthetically and functionally efficient surgical correction is proposed.